Pilot Fountain Pen Converter (CON-70)

using with pilot kakuno.... had zero issues. I bought syringes to refill with after reading some reviews saying the pump function doesn't work. mine worked fine. I ended up with quite a few air bubbles in mine. ... but it writes smoothly. far better with my new hongdian ink than the namiki disposable cartridges. I think the problem may also be removed by taking more care when filling it. i.e. making sure the nib is completely submerged... holding the pen either straight up and down, or at a slight angle. relieving the depressor very slowly.... I need to experiment.... I just pumped it 5 times at first and it barely filled it. did it probably 5-8 more times and then I felt one pump with slight pressure that wasn't there before and stopped. it definitely looks full. even if I do wind up having to use the syringes I'd be happy with this set up .. but unless I find out the airbubbles can't be fixed and are an issue I don't think there is anything bad to say. al

The CON-70 converter is the most ink you can put into your Pilot fountain pen (except for piston filler or vacuum filler pens).CON-70 = 1.06 mlCartridge = 0.90 mlCON-B = 0.62 mlCON-40 = 0.61 mlThe CON-70 converter works similarly to a vacuum filler. Pushing the button down pushes the diaphragm down towards the mouth of the converter, and creates a vacuum behind the diaphragm. Near the end of the stroke, the diaphragm breaks contact with the interior walls of the converter tube, causing whatever in front of the diaphragm to get sucked back behind the diaphragm. When it's installed in the pen, and the nib is submerged in the ink bottle, it will cause some of the ink to get drawn up behind the diaphragm. Pushing the button down quickly (and then releasing it) three to five times will get you a nearly completely full filling. A little bit of air will always be there, but it should be less than a 5th of the total volume.I use mine in my Pilot Silvern pen; that pen comes with a CON-40, but you CAN put a CON-70 in it...as long as you remember to point the nib up before screwing the back of the pen back on. It's a little bit too long for that pen, and the button gets pushed in just a little bit. But since air rises to the top of a liquid, only air and some bubbles will come out of the nib. Just wipe it off, and write on.

Don't know why some people don't like these. They hold more than regular converters and are quite easy to clean. The push button is easier and clear than twisting the knob on conventional converters. Almost like a Vac fill. Just hold the pen vertical. With the same hand, push the button a few times and you are done. Easier to fill and cleaner.

I'm using this converter in a Pilot Kakuno and have had no problems. Loving the extra capacity of ink and extending pen use a couple days past when using smaller converters. No leaking.

It fit in the pen well. There was some leakage. However, it could've just been my pen's quality. The converter kept up with my writing speed. I don't think the value is great for the money I paid though.

I now love my kakuno even more!!! Bravo!

why it wasn't holding more? I looked closely and something had disconnected inside the mechanism. so it sucks up only a small amount of ink. I was able to turn it upside down and fill it with a dropper Great capacity- plunger broke with normal use. not how it is supposed to work

I purchased this converter for the Pilot Kakuno fountain pen. It fits and works properly.